Novel carbamate antistatic agents

ABSTRACT

NEW COMPOUNDS WITH ANTISTATIC PROPERTIES ARE PROVIDED. THE NEW COMPOUNDS ARE CARBAMATES AND QUATERNARY DERIVATIVES THREOF, WHICH IN THEIR BASE FORM ARE REPRESENTED BY THE FORMULA I: R4-(R5-)N-(1,4-PHENYLENE-O)M-(CH2-CH(-X)-O)N-CO-NH-(CH2)3N(-R1)-R2 WHEREIN R4 AND R5 ARE ALKYLF X IS HYDROGEN, METHYL OR ETHYL; R1 AND R2 ARE INDIVIDUALLY ALKYL OR HYDROXYALKYL: N IS AN INTEGER OF FROM 1-10; AND M IS 0 TO 1. THE QUATERNARY COMPOUNDS ARE THE HYDROXYALKYLAMMONIUM DERIVATIVES SUCH AS THOSE OBTAINED BY HEATING THE COMPOUNDS OF FORMULA I WITH AN ALKYLENE OXIDE IN THE PRESENCE OF AN ACID. TYPICALLY, THE COMPOUNDS OF THE INVENTION ARE APPLIED BY DIPPING AN ARTICLE, SUCH AS A FIBER, INTO A SOLUTION OF THE CARBAMATE IN A SUITABLE SOLVENT. REPRESENTATIVE ANTISTATIC AGENTS OF THE PRESENT INVENTION ARE PREPARED BY THE REACTION OF PHOSGENE WITH AN ETHOXYLATED DIALKYLAMINE, GIVING A CHLORCARBONATE WHICH IS THEN REACTED WITH N,N-DIMETHYLPROPYLENEDIAMINE IN SUFFICIENT QUANTITIES TO FULLY REPLACE ALL THE CHLORINE.

United States Patent O 3,658,882 NOVEL CARBAMATE ANTISTATIC AGENTS Fred S. Eiseman, Jr., Maplewood, N.J., assignor to GAF Corporation, New York, N.Y. No Drawing. Filed May 18, 1970, Ser. No. 38,517 Int. Cl. C07c 125/06 U.S. Cl. 260-482 C 4 Claims ABSTRACT OF THE DISCLOSURE New compounds with antistatic properties are provided. The new compounds are carbamates and quaternary derivatives thereof, which in their base form are represented by the Formula 1:

wherein R and R are alkyl; X is hydrogen, methyl or ethyl; R and R are individually alkyl or hydroxyalkyl; n is an integer of from 1-10; and m is to l. The quaternary compounds are the hydroxyalkylammonium derivatives such as those obtained by heating the compounds of Formula I with an alkylene oxide in the presence of an acid. Typically, the compounds of the invention are applied by dipping an article, such as a fiber, into a solution of the carbamate in a suitable solvent. Representative antistatic agents of the present invention are prepared by the reaction of phosgene with an ethoxylated dialkylamine, giving a chlorocarbonate which is then reacted with N,N-dimethylpropylenediamine in sufiicient quantities to fully replace all the chlomm.

This invention relates to new compounds which function as antistatic agents when coated on polymeric substrates. It relates further to new N-aminopropyl-carbamates and quaternary derivatives thereof which can be prepared by the reaction of certain chlorocarbonates with certain substituted propylenediamines, and then optional quaternization. It relates still further to the use of such carbamates to render polymeric materials resistant to static charge build-up. The carbamates of this invention are represented by the general Formula 1:

wherein R and R are alkyl groups of 1-18 carbons and preferably 4-6 carbons (such as butyl and cyclohexyl), the total of both being at least 4; X is hydrogen, methyl or ethyl; n is an integer from 1 to m is 0 or 1; and each of R and R is individually a member of the group consisting of alkyl and hydroxyalkyl radicals of l-3 carbon atoms such as methyl, ethyl, isopropyl, propyl, hydroxyethyl, dihydroxypropyl, etc. The monoand di-quaternary ammonium derivatives are prepared by treating the compounds of Formula I with an alkylene oxide under acidic conditions. Either or both tertiary nitrogens can be quaternized by substitution of an hydroxyalkyl radical in this manner.

When fibers, especially those prepared from synthetic polymers, are subjected to frictional forces such as those encountered in textile mills during spinning of the fiber into yarn, and weaving of fabric or rugs from the yarn, or during the use of the resultant articles as they are handled, flexed and rubbed, static electricity is generated. The attractive forces exerted upon the charged fibers interfere with their movement through spinning and weaving equipment and cause unwanted dust and lint accumulations. Additionally, fabrics which retain their static charge tend to adhere to other surfaces and, in the case of clothing, this presents an unsightly apperance which detracts from the value thereof.

Not all materials generate static electricity equally. Under normal humidity conditions, viscose rayon does not generate static electricity to any great extent. Acetate rayon and wool generate static electricity to such a small extent that the problem can be controlled by maintenance of high humidity in the mill rooms. Polyester, acrylic and vinyl fibers are notoriously efficient static charge generators and it is known to treat them with antistatic agents, generally added to fiber lubricants which are applied to the fiber surfaces during processing, Such antistatic agents are generally not durable and cease to be capable of providing antistatic activity after the fabric is washed.

The problem of finding an efiective, durable antistatic agent for synthetic fibers polymers has been extensively investigated. Antistatic agents function in two general Ways, both of which improve the electrical conductivity of the fiber surface. They are either reasonably good conductors of electricity themselves or they are hygroscopic and help concentrate atmospheric moisture on the fiber. This latter type includes many of the polyhydroxy and polyethyleneoxy compounds.

The majority of antistatic agents fall into one of the following three structural categories: (1) non-ionic polyhydroxy and polyalkyleneoxy compounds; (2) cationic or neutral nitrogenous compounds with a hydrophobic moiety in their structure, e.g., long chain amines or quaternary ammonium compounds; (3) long-chain phos phates, phosphonates, or other oxygenated phosphorus derivatives. Additional types include sulfonated oils and ester emulsions, and other fiber lubricant emulsions which depend on the particular emulsifying agent used for their antistatic effect.

Long chain quaternary ammonium salts have a marked antistatic action and are widely used in this capacity. These quaternaries are frequently used in combination with auxiliary agents which may themselves be antistatic agents or serve the secondary purpose of binding the finish to the fiber, as disclosed in U.S. 2,463,282. The water insoluble salts of higher amines together with polystyrene sulfonates are described in U.S. 2,700,001 as nylon antistats, Phosphorus compounds with antistatic capacities are described in U.S. 2,575,382; 2,575,399 and 2,676,122. Hygroscopic salts, such as cyclohexylarnine lactate, are disclosed in German Pat. 840,694, while the use of polyethoxylated fatty acids and alcohols as antistatic agents for polypropylene articles as Well as fibers is reported in U.S. 2,525,691.

It is a primary object of the present invention to provide a new class of chemical compounds. It is another object of this invention to provide a new class of antistatic agents. It is a further object to provide a means of preventing the accumulation of static electricity on the surfaces of articles prepared from synthetic organic polymers. Still other objects will appear from the following description of this invention.

The compounds of the present invention in their base form are represented by general Formula 1 given above. These carbamates as well as their monoand diquaternary ammonium derivatives, show excellent antistatic properties when applied to synthetic fibers. They impart not only the antistatic properties associated with an amide linkage, but also the desirable antistatic characteristics of the polyethoxylated hydrophobe. Unexpectedly the combination of these chemical structures within the carbamate molecular structure provides an enhancement of antistatic activity lacking through the simple admixture of nonionic and amide type antistatic agents.

The antistatic agents of the present invention can be applied by dipping, spraying, wiping or brushing a solution or dispersion of the material in a suitable medium. The amount to be applied depends upon the intended use of the article as well as the inherent characteristics of the plastic material. The persistence of the charge on the surface of the plastic is mainly attributable to the fact that plastics have very high surface resistance, in the order of as high as ohms per square. The antistatic agent operates by lowering the surface resistance to the point where the static charges are dissipated in a relatively short time. However, since the plastic is essentially nonconductive, electrostatic charges may be distributed quite irregularly over the surface and it is therefore essential that the antistatic agent be applied in sufficient concentration to provide an intact coating over the entire surface. Since the formation of static electricity is essentially a surface phenomenon, the amount of antistatic agent to be applied depends upon the total surface area of the article to be treated rather than its weight. In the case of thin films and high denier fibers, the antistatic coating may constitute 50% or more by weight of the coated material. That is to say, if a plastic film of about 1 mil thickness is to be treated and the antistatic agent does not readily form films thinner than about 1 mil, the treated plastic may contain at least 50 percent by weight of antistatic agent. 0n the other hand, if it is desired to treat a molded article such as a plastic dial face with antistatic agent, the coating may constitute no more than about 0.05% by butyl H P O4 butyl weight of the entire article. Without intending to limit the present invention to named weight proportions of antistatic agent to treated polymer, application rates in the range of about 0.05% to 10.0% are generally useful in the treatment of fabrics and thin films to impart antistatic properties thereto.

The antistatic agents of the present invention can be used to treat organic polymeric fibers, films or other articles of manufacture to prevent the accumulation of surface static charge. The action of the antistatic agent is independent of the chemical nature of the polymer and any polymer can be treated, including polyesters (e.g., those of phthalic and terephthalic acid with glycols such as ethylene glycol); vinyl polymers (e.g. polyvinyl chloride and polyvinyl alcohol); polyolefins (e.g. polyethylene and polypropylene); polyamides (e.g. nylon); acrylics (e.g. polymethyl methacrylate and polyacrylonitrile); and other such as the polyacetals, the polycarbonates, the polyepoxides, and the like.

The antistatic agents of the present invention form durable coatings on the surface of plastic materials. They have a sufficiently high vapor pressure tobe resistant to loss by evaporation under normal conditions. They are not readily removed by dry wiping and they have relatively high resistance to removal by washing with aqueous solutions. By use at relatively high application rates, they can provide protection against static charge build-up for extremely long periods under relatively adverse conditions.

The compounds of Formula I wherein n is 1 can be prepared by reacting a dialkylaminoethanol or dialkylaminophenol with phosgene to form the corresponding chlorocarbonate, and reacting the latter compound with a dialkylaminopropylamine. If the ethoxylated derivatives of Formula I (i.e. wherein n is greater than 1) are desired, the dialkylaminoethanol or dialkylaminophenol is reacted with l-l0 moles of ethylene oxide before the reaction with phosgene. The monoand di-quaternary ammonium derivatives are readily obtained by treating the compounds of Formula I with an alkylene oxide under acidic conditions. Suitable alkylene oxides are ethylene oxide, propylene oxide and butylene oxide. Suitable acidic materials are hydrochloric, hydrobromic, phosphoric, nitric and sulfuric acids.

In the preferred synthesis, a dibutylaminoethanol is used as the dialkylaminoalcohol. However, this material may be reacted with an alkylene oxide using an alkaline catalyst at l20150 C. and 1-30 p.s.i.g. until one to ten moles of the oxide is added. In place of the alkaline catalyst, acidic catalysts such as BF H PO and the like can be used. Other dialkylamino alcohols as well as dialkylaminophenols such as dimethylaminophenol, diethylaminophenol, etc., can be substituted for the dibutylaminoethanol. The resultant dialkylamino or dialkylaminophenoxy polyalkyleneoxyalkanol is then reacted with phosgene to form the corresponding chlorocarbonate, and the latter compound converted to its carbamate by reaction with gamma dial'kylaminopropylamine. This latter derivative may then be acidified and reacted with an alkylene oxide to form its quaternary ammonium salt or di-quaternary ammonium salt.

The effectiveness of antistatic agents is judged on the basis of their ability to reduce the resistivity of the polymers they are used to treat. The test method which was used in evaluating the antistatic agents of this invention is AATOC Standard Test Method 76-1959.

The following examples are presented to further illustrate the present invention. Therein, unless otherwise stated, parts and percentages are on a weight basis.

EXAMPLE I (a) To a round bottom flask was charged a total of 173 parts of dibutylaminoethanol and 175 ml. of dioxane. The ethoxylate was agitated at ambient temperature (20- 30 C.) while phosgene was bubbled in under the surface over about 1.5 to 2.0 hours. Addition of phosgene was continued until IR examination of a sample showed that essentially all absorption due to the hydroxyl group was eliminated.

(b) To a beaker equipped with agitator, two dropping funnels, thermometer and a pH meter were charged 400 ml. of water and 92 gms. of dimethylpropylenediamine (0.9 mole). These materials were agitated at room temperature while 387 gms. of the N,N-dibutylaminoethyl chlorocarbonate (0.9 mole) in dioxane prepared in (a) and 30% NaOI-I were dropped in simultaneously over about 1 to 1.5 hours at such a rate as to maintain the pH between 10.0 to 10.5. A total of 208 gms. of 30% NaOH was required. After all reactants were added the batch was agitated 15 minutes at rooni temperature and then brought to pH 9.0 with CP HCl. A total of 65 gms. was required. The product, N,N-dibutylaminoethyl N-(3-dimethylaminopropyl)carbamate was then stripped of water and dioxane, at 40 mm. pressure and the residue was filtered. The yield was 217 gms. (79.5% of theoretical).

(c) To a 1 liter 4 necked flask with joints clamped for slight pressure were charged gms. (0.6 mole) of the above carbamate, 200 ml. of H 0 and 180 gms. of B 1 0 to bring pI-l to 3.0 to 3.5. The materials were agitated at 50-60" C. and purged with N Ethylene oxide (56 gms. from cylinder) was added. A total of 51 gms. was absorbed.

The resultant quaternary ammonium product was stripped to 110 C. pot temperature under line vacuum and then filtered. The weight of the final product was 320 gms.

(d) The quaternary formed above was applied from MeOHlCCh, (520 mls.]l000 mls.) solvent mixture to nylon faille and polypropylene swatches at a 2.50% ap- Log ohms I square Nylon Polyfaille propylene Control 13.66 14. e4 Quaternary carbamate- 9. 41 9. 12

EXAMPLE H Log ohms 1 square Nylon faille Orlon Control 13. 66 14. 24 Carbamate 8. 57 8. 73

EXAMPLE III (a) To a round bottom flask was charged a total of 253 parts of an ethoxylate (1.64 moles of ethylene oxide) of dicyclohexylamine in 200 gms. of dioxane. The ethoxylate was agitated at 60 C. while phosgene was bubbled in under the surface over about 1.5 to 2.0 hours. Addition of phosgene was continued until examination of the sample under IR showed essentially all absorption due to the hydroxyl group was eliminated.

(b) To a beaker equipped with agitator, two dropping funnels, thermometer and a pH meter were charged 400 ml. of water and 117 gms. of diethylpropylenediamine (0.9 mole). These materials were agitated at room temperature while 466 gms. of the chlorocarbonate (0.9 mole) in dioxane prepared in part (a) of this example and 30% NaOH were dropped in simultaneously over about 1 to 1.5 hours at such a rate as to maintain the pH between 10.0 and 10.5. A total of 147 gms. of 30% NaOH was required. After all reactants were added the batch was agitated 15 minutes at room temperature and then brought to pH 9.0 with CP HCl. A total of 89 gms. was required. The product was then stripped of water at 40 mm. pressure and the residue was filtered. The yield was 307 gms. (82% of theory) of dicyclohexylaminoethoxyethyl N-(S-diethylaminopropyl) carbamate.

(c) To a 1 liter 4 necked flask with joints clamped for slight pressure were charged 246 gms. (0.6 mole) of MeOHICCh (520 mls.l1000 mls.) solvent mixture to Orlon acrylic and polypropylene swatches at 2.50% application rate according to AATCC Standard Test Method 76-1959.

The swatches were conditioned at 72 F. and 50% relative humidity for at least 24 hours and the resistivity measured. Results were as follows:

Log I ohms[square (a) To a round bottom flask was charged a total of 439 parts of an ethoxylate (4.6 moles of ethyleneoxide) of di-(2-ethylhexyl)amine in 300 gms. of dioxane. The ethoxylate was agitated at 50-60 C. while phosgene was bubbled in under the surface over about 1.5 to 2.0 hours. Addition of phosgene was continued until examination of sample on IR showed essentially all absorption due to the hydroxyl group was eliminated.

(b) To a beaker equipped with agitator, two dropping funnels, thermometer and a pH meter were charged 200 ml. of water and 92 gms. of dimethylpropylenediamine (0.9 mole). These materials were agitated at room temperature while 452 gms. of the chlorocarbonate (0.9 mole) in dioxane prepared in (a) and 30% NaOH were dropped in simultaneously over about 1 to 1.5 hours at such a rate as to maintain the pH between 10.0 to 10.5. A total of gms. 30% NaOH was required. After all reactants were added the batch was agitated 15 mins. at room temperature and then brought to pH 9.0 with CP HCl. The product was then stripped of water at 40 mm. pressure and the residue was filtered to yield 448 gms. (88.0% of theory) of the carbamate.

(c) The carbamate product was applied from MeOHICCh (520 mls.|l000 mls.) solvent mixture to nylon faille and polypropylene swatches at a 2.50% application rate according to AATCC Standard Test Method 76-1959.

The swatches were conditioned at 72 F. and 50% relative humidity for at least 24 hours and the resistivity measured. Results were as follows:

Log ohms I square N y pn Polyiallle propylene Control 13. 66 14. 64

Carbamate... 9. 39 9. 51

EXAMPLE V (a) To a round bottom flask was charged a total of 225 parts of an ethoxylate (2.0 moles of ethyleneoxide) of pdimethylaminophenol in 250 ml. of dioxane. The eth oxylate was agitated at 40-50 C. while phosgene was bubbled in under the surface over about 1.5 to 2.0 hours. Addition of phosgene was continued until examination of sample on IR showed essentially all absorption due to the hydroxyl group was eliminated.

(b) To a beaker equipped with agitator, two dropping funnels, thermometer and a pH meter were charged 400 ml. of water and 91 gms. of dimethylpropylenediamine (0.9 mole). These materials were agitated at room tem perature while 485 gms. of the chlorocarbonate (0.9 mole) in dioxane prepared in (a) and 30% NaOH were dropped in simultaneously over about 1 to 1.5 hours at such a rate as to maintain the pH between 10.0 to 10.5. A total of 130 gms. of 30% NaOH was required. After all reactants were added the batch was agitated 15 minutes at room temperature and then brought to pH 9.0 with CP HCl. The product was then stripped of water at 40 mm. pressure and the residue was filtered to yield 277 gms. (87% of theoretical) of the desired carbamate.

(c) To a 1 liter 4 necked flask with joints clamped for slight pressure were charged 212 gms. (0.6 mole) of the above carbamate, 200 ml. of H and 164 gms. of CF. HCl to bring pH to 3.0 to 3.5. Materials were agitated at 50-60 C. and purged with N Propylene oxide was added until total of 66 gms. was absorbed.

The reaction mixture was stripped to 110 C. pot temperature under line vacuum and then filtered giving 277 gms. of the desired hydroxypropyl quaternary ammonium chloride.

(d) The quaternary formed above was applied from MeOI -IICCL, (520 m1s.|1000 mls.) solvent mixture to Orlon acrylic and polypropylene swatches at 2.50% application rate according to AATCC Standard Test Method 76-1959.

The swatches were conditioned at 72 F. and 50% relative humidity for at least 24 hours and the resistivity measured. Results were as follows:

Log ohms square 8 What is claimed is: 1. A carbamate or quaternary ammonium derivative thereof which in its base form is represented by the forwherein R and R are alkyl groups of 1-18 carbons, the total of both being at least four; X is hydrogen, methyl or ethyl; n is an integer of from 1 to m is 0 or 1; and each of R and R is individually a member of the group consisting of alkyl and hydroxyalkyl of'1-3 carbon atoms, wherein the mono and (ii-quaternary ammonium derivatives are obtained by treating the compound of the above formula. with alkylene oxide under acidic conditions said alkylene oxides being ethylene oxide, propylene oxide and butylene oxide, and said acidic materials being hydrochloric, hydrobromic, phosphoric, nitric and sulfuric acids.

2. A compound of claim 1 wherein m is 0.

3. A compound of claim 1 wherein m is 1.

4. A compound of claim 1 wherein n is l.

JAMES A. PATTEN, Primary Examiner P. J. KILL-OS, Assistant Examiner US. Cl. X.R. 

